The present invention relates to a system for connecting releasingly two elements with each other, comprising a male part being integral or connectable with a first element, and a female part being integral or connectable with the second element, wherein one of the parts, the male or female one, has a round section and is provided with a screw thread and the other part is provided with at least one protruding tooth, being engaged into the screw thread with the male and female parts being inserted into each other.
Such a connecting system is generally known. In practice, a metal part is used on the one hand, and on the other hand, a synthetic part having such a shape that the synthetic part or at least parts thereof can be elastically or plastically distorted. So-called nail plugs are well known, being made of a synthetic sheath-shaped part in which inwardly protruding edges are formed, and a nail or dowel part partially provided with a screw thread. After sticking the nail part into the sheath, the nail part may be unscrewed again. However, the sheath is not to be used again since it has suffered from permanent damages. When sticking the nail part, quite strong forces are applied.